Spraying apparatus



June 8, 1937. E. M. sEARLs SPRAYING APPARATUS Filed Jan. 18, 1988ATTO/P/VEYS Patented June 8, 1937 UNITED sTATEs PATE-rj ricE SPRAYINGAPPARATUS Edward M. Searls, Madison, Ws Application January 13, 1988,seriaiNo. 58,837.

4 olaims. (ol. 2994-96) 2 w' I an inwardly opening check valve 23 and anoutw This invention relates to spraying apparatus, and in particular, toportable sprayers such as may be carried upon the back of the operator.

One object of this invention is to provide a 5 portable sprayer, like aknapsack, wherein the fiuid container and pump are arranged on the backof the operator, the pump being operated by a forwardly extending lever,and the fluid being sprayed in any desired direction by a nozzleconnected to the fluid container by a flexi'ble Another object of thisinvention is to provide such a spraying apparatus, wherein adoubleacting pump is employed to produce a steady source of compressedair, this being conveyed to the spray nozzle by a separate path from thefluid.

Another object is to provide a ri'gid support arranged to be held on theback of the operator by straps, this support carrying an air pump and afluid container as well as a bracket serving as a fulcrum for the handlever by which the pump is operated, the sprayer preferably includingseparate conduits for air and for liquid, so as to atomize the liquid atthe nozzle by the action of the air.

In the drawing:

Figure 1 is a perspective view of the spraying apparatus of thisinvention.

Figure 2 is an enlarged side e1evation,'partly in longitudinal section,of the spray nozzle of this invention. i

Referring to drawing in detail, Figure 1 shows the spraying apparatus ofmy invention as including a base plate IO, which is arranged to bemounted upon the back of the operator, and to this end is supplied witha back rest I I mounted at the lower edge of the base plate I. Securedto the back rest l I, which rests against the lower portion of the backof the operator, are clips l2 providing anchorages for straps l3 and |4.The straps [3 encircle the waist of the operator and serve to hold thesprayer in position against his back, whereas the straps Ill pass overhis shoulv ;355.bolt |8. The upper. end capI 2|v is provided with wardlyopening check valve 25, to' the latter. of which isattached the flexibleconduit 23 leading to one' arrnof the T-connection 21. Similarly, thelower end cap- 22 is provided with an inwardly opening 'check vValve 28'and an out- Wardlyiopening check Valve 29, to the latter of whichis'joined the fiexible conduit 30, likewise leading toanother arm of theT-connection 21. The lower end cap 22 is also provided with a gland 3|,through which passes the pump piston rod 32.

On the end of the piston rod 32, Withinthe pump cylinder 20, is'aVpiston (not shown). To the lower end of the piston rod 32 is threaded aclevis 33, this being locked in position by the locknut 34. A coilVspring 35, encircling the piston rod 32, serves to absorbthe shockwhich might otherwise voccur in the event that the clevis 33 encounteredthe gland 3 l. In the slotted f' portion 36 of the cleVis 33 is mountedone end of the hand lever 31 bymeans of vthe pivot screw 38. The1ev'r43'l vis =-pivotal1y secured to the apparatus by means-lof 'thef-ulcrum bolt 39, which is threaded into the angle vbracket ll, theoppo- ;i site end of which is secured to the 'base plate Ill.

'The arm'M, extending forwardly from the base to the base plate VIll andserves as a bottom rest w for the container 43, whereas a holder 45,consisting'of a U-shaped brace encircling the container 43,7engages thecontaner 43 at an intermediate point and holds it in` position againstthe base plate IB. .The mouth of the container is closed by. a topmember ll, screwed, bolted or otherwise suitab-ly secured to thecontainer 43.

Inthe form shown this top member 43 forms a chamber above the container;The-'third arm of the T-connection 21 passes through the upper end ofthe top member 43, into the chamber -itherein sov as to discharge airfrom the airpump |9 into the top member 46, and thence into thecontainer 43. Through the top member 46 also V ,passes the tubularconnection 41, with its end opening directly into the Chamber of the topmember 46, exactly as in the case of the T-connection 21. The third tube4B passes downwardly through the upper part of the top member 46,

5 into the container 43, and has mounted on its lower end a flexibletube 49 through which the liquid passes on its way to the spray nozzle.

Attached to the air connection 41 is an air pipe 50, of fiexiblematerial such as rubber, and connected to the rigid pipe 5| leading tothe nozzle, generally designated 52. Similarly, to the tube 48 isconnected a flexible pipe 53 leading to the rigid pipe 54, the latterbeing likewise connected to the spray nozzle 52.

Referring more particularly to Figure 2, the nozzle 52 is seen tocomprise a barrel 55, threaded at both ends. On the forward end of thebarrel 55 is mounted the nose cap 56, While on the rearward end isthreaded the coupling member 51.

The midportion of the barrel 55 is provided with a threaded aperture 58for receiving the correspondingly threaded end of the pipe 5|. Arrangedwithin the barrel 55 and threaded into one end of the coupling 51, isthe inner nozzle member 59 having a central bore 60. The inner nozzlemember 59 is of reduced diameter, as compared with the inner diameter ofthe barrelr55, and is provided with projections 6| serving as spacingmembers to maintain the inner nozzle member 59 in proper position Withinthe barrel. Into the outer end of the inner nozzle member 59 is threadedthe nozzle tip 62, having a forwardly tapering portion 63 forming aconical converging space in cooperation with the inner v'-35 wall 64 ofthe nose cap 56. Due to the fact that the conical surfaces 63 and 64converge by different amounts, the space between them forms a taperingannular conical passageway for the air on its way outward through thespace between '40 the tip 62 and the nose cap 56.

Threaded into the rearward end of the coupling 51 is the nipple 65, theopposite end of which is threaded into the forward portion 66 of thevalve casing 61. The forward portion 66 45 is provided with a conicalvalve seat 68, whichis 50 1 I, this being threaded into the rearwardportion 12 of the valve casing 61. The hollow nut 13 is threaded ontothe outer endof the valve stem support 1|, and contains a packingencircling the valve stem 10 and arranged to prevent leakage 55 aroundthe valve stem. A hand wheel 14 secured to the outer end of the valvestem 10 serves to turn the latter, and accordingly to move the needlevalve portion 69 toward or away from its conical seat 68, therebyregulating the amount 60 of fluid which will pass into the nozzle.Threaded onto the upper portion 15 of the valve casing 61 is a cap` 16,which holds a threaded adapter 11 arranged to receive thecorrespondingly threaded end of the pipe 54.

G5 In the operation of the spraying apparatus of this invention, thecontainer 43 is filled or partially filled with a suitable amount of`spraying fiuid, this fluid being either an insecticide or any otherliquid which is suitable for spraying, such 70 as paints, varnishes,antiseptic or disinfectant solutions, etc.

The operator straps the device upon his back with the straps |4 over hisShoulders and the strap |3 around his waist, and carries the ap- 0 75paratus to the place where it is intended to be used. To use theapparatus the operator moves the handle 42 up and down, thereby causingthe' double-acting air pump E9 to pump air through the T-connection 21into the top member 46, above the container 43. This air exerts pressureupon the top surface of the liquid, forcing a portion of it upward intothe tube 49, and thence outward through the tube 48, the flexible pipe53 and rigid pipe 54, into the valve casing 61, and thence outwardthrough the central bore 60 and the tip 52 of the nozzle 52. At the sametime air passes from the top member 46, through the tubular connection41, the fiexible pipe 59 and the rigid pipe 5! to the Chamber within thebarrel 55 of the nozzle 52, thence passing outward through the annularconical passageway between the nose cap 56 and the nozzle tip 62. Byscrewing the nose cap 56 in or out, and by regulating the hand wheel 14,the quantity and quality, as regards physical condition, of the spraymay be readily adjusted, and the nozzle adapted to the effectiveatomization of liquids of various viscosities and bcdies.

The apparatus of this invention, when properly adjusted, is capable ofproducing homogeneous sprays consisting of globules varying from 10 to360 microns in diameter according to the purpose and wishes of theoperator, from oils varying in viscosity from 34 to 110 Saybolt test at100 F. when operated at a pressure of 10 to 15 pounds per square inch.Dissolved in the distillate is a toxic agent, such as pyrethrum, thismixture being used where an insecticide is to be sprayed onto plants. Bythe atomizing action of the apparatus of this invention, the fluid isdistributed well over the plant leaves and the oil penetrates to hiddencrevices so as to kill the insect life thereon, especially with the useof liquids having low surface tensions, such as hydrocarbon oils.

The sprayer of this invention is also equally effective whether thenozzle is directed upward or downward, in contrast with certain types ofhand-operated sprayers which are inefficient except when they are usedin a horizontal position. The connection-of the flexible air pipe 50 tothe tubular connection 41 on the opposite side of the top member 46 fromthe T-connection 21 causes the pulsations of the double-acting pump 19to be smoothed out by the cushioning effect of"the air within theChamber inside the top member 46.

By thus separately conducting the air and liquid to the nozzle, I causethe air to act upon and atomize the liquid into a mist-like spray. Thisspray is given the desired direction by the nozzle, and requires only arelatively low air pressure to do this. The usual sprayer, however,conducts only the liquid to the nozzle, and the latter is required notonly to direct the spray but also to produce it by mechanical action,thereby requiring a relatively higher pressure and producing largerglobules of liquid in the spray.

It will be understood that instead of a glass container, as shown, ametal container migh't also be used for the fiuid.

It will further be understood that it is desired to comprehend withinthis invention such modifications as come within thescope of my claimsand my invention.

I-Iaving thus fully described my invention, what I claim as new anddesire to secure by Letters Patent, is:

1. An atomizing and spraying apparatus comprising a support adapted tobe mounted on the back of the operator, a pump on said support, a-

` fiow and atomization of the fiuid at low presliquid container on saidsupport, an atomizing and spraying nozzle, an air-conducting conduitconnected to said pump and arranged to discharge air into the spaceabove thelliquid in said liquid container, a liquid-conducting conduitwith one end opening beneath the level of said liquid and the otherendconnected to said nozzle, and a separate air-conducting conduitconnecting the space above the level of the liquid in said containerwith said atomizing and spraying nozzle, the said air-conducting conduitfrom said pump to said container having a separate connection theretofrom said air-conducting conduit connecting said container With saidnozzle, whereby the air space above the level of the liquid in saidcontainer and the said separate connections thereof serve to damp thepulsations of the pump and to promote the even fiow and atomization ofthe fluid at low pressures.

2. An atomizing and spraying apparatus comprising a support adapted tobe mounted on the back of the operator, a double-acting pump on saidsupport, a liquid container on said support, an atomizing and sprayingnozzle, an air-conducting conduit connected to said pump and arranged todischarge air into the space above the V liquid in said liquidcontainer, a liquid-conducting conduit With one end opening beneath thelevel of said liquid and the other end connected to said nozzle, and aseparate air-conductin'g conduit connecting the space above the level-ofthe liquid in said container with said atomizing and spraying nozzle,the said air-conducting conduit from said pump to said container havinga separate connection thereto from said airconducting conduit connectingsaid container with said nozzle, Whereby the air space above the levelof the liquid in said container and the said separate connectionsthereof serve to damp the 40 pulsations of the pump and to promote theeven sures.

3. An atomizing and spraying apparatus comprising a support adapted tobe mounted on the back of the operator, a pump on said support, a liquidcontainer on said support, an upper chamber associated with said liquidcontainer, a plurality of independent air connections opening into saidupper chamber, an air conduit connecting said pump with one of saidconnections, an atomizing and spraying nozzle, an air conduitinterconnecting said nozzle'with the other of said air connections ofsaid chamber, and a liquidconducting conduit having one end openingbeneath the level of said liquid and the other end connected to saidnozzle, whereby the chamber With its separate air connections serves asan air cushion to damp the pulsations of the pump and to insure an evenand continuous flow of atomized fluid at low pressures. i

4. An atomizing and spraying apparatus comprising a support adapted tobe mounted on the back of the operator, a double-acting pump on saidsupport, a liquidrcontainer on said support, an upper chamber associatedwith said liquid container, a plurality of independent air connectionsopening into said upper chamber, an air conduit connecting said pumpwith one of said connections, an atomizing and spraying nozzle, an airconduit interconnecting said nozzle with the other of said airconnections of said chamber, and a liquid-conducting conduit having oneend opening beneath the level of said liquid and the other end connectedto said nozzle, whereby the chamber with its separate air connectionsserves as an air cushion to damp the pulsations of the pump and toinsure an even and continuous fiow of atomized fiuid at low pressures.

EDWARD M. SEARLS.

